ok guys, the Yammie DXN is down, need your thoughts.

[czac]

so I finally got a new DG exhaust set up off ebay for a good price and went to take off the stock head pipe on my DXN 225, both bolts were stripped and the allen wrench just slipped around inside it so I used a "rounded" bold remover and got one out, the second one, the harder of the two to reach, wasnt as easy, the bold broke off leaving me just enough sticking out to grab with a vise grip but couldn't turn it cause it hit the fins on the head.
long story short, I broke the casting around the bolt.

luckily I had a seized motor in the garage with a good (well, not busted) head on it. I took it off and cleaned it, everything looked good so I put it on my motor, re did the timing, adjusted the valves and all but now the bike wont start.
it starts and runs only with starter fluid sprayed into the spark plug hole and will run on the fluid for a second or two but thats it.
I took the carb off and cleaned it and tried a newer main jet that was the same size but still got nothing,
I tried disconnecting the air intake figuring it may have been chocking out, nothing...
I even pulled the baffle out of the new tail pipe... still wont start.
Any thoughts?

I know sometimes you may have to re jet the carb with these aftermarket pipes... but it runs on the starting fluid. Its almost like its not getting gas into the cylinder but the Spark plug is wet when I take it out.
Could it be the air mix screw maybe?
I usually run it 1-1/2 turns out with the stock pipe and even when I had the YZ 250 muffler on it... maybe I should try 2 or 3 turns? :confused:

[Ghostv2]

I would recheck timing and adjust your valves once again. They can easily prevent it from starting. That was the last problem I had with my DX. Valves were too tight causing it to not start with the electric start but would pop off with the recoil. They can be finicky but once you get them right they are reliable as heck.

Because even when I switched to a DG exhaust on mine it still ran with stock jetting, stock air box, etc.

Hell it even ran with stock jets and a pod filter. Poorly, but would still start up no problem.

[yaegerb]

so I finally got a new DG exhaust set up off ebay for a good price and went to take off the stock head pipe on my DXN 225, both bolts were stripped and the allen wrench just slipped around inside it so I used a "rounded" bold remover and got one out, the second one, the harder of the two to reach, wasnt as easy, the bold broke off leaving me just enough sticking out to grab with a vise grip but couldn't turn it cause it hit the fins on the head.
long story short, I broke the casting around the bolt.

luckily I had a seized motor in the garage with a good (well, not busted) head on it. I took it off and cleaned it, everything looked good so I put it on my motor, re did the timing, adjusted the valves and all but now the bike wont start.
it starts and runs only with starter fluid sprayed into the spark plug hole and will run on the fluid for a second or two but thats it.
I took the carb off and cleaned it and tried a newer main jet that was the same size but still got nothing,
I tried disconnecting the air intake figuring it may have been chocking out, nothing...
I even pulled the baffle out of the new tail pipe... still wont start.
Any thoughts?

I know sometimes you may have to re jet the carb with these aftermarket pipes... but it runs on the starting fluid. Its almost like its not getting gas into the cylinder but the Spark plug is wet when I take it out.
Could it be the air mix screw maybe?
I usually run it 1-1/2 turns out with the stock pipe and even when I had the YZ 250 muffler on it... maybe I should try 2 or 3 turns? :confused:

Check spark, should be fat and blue.

[El Camexican]

- Does it have a crisp blue spark? (I suspect it does if it fires on ether)
- Any backfires out of the carb or pipe?
- Is you choke working? (they won't start without it in cold weather)
- Check the compression (if its low you may be off a tooth on the cam, or have a bent or over tightened valve)

If I had only one guess at this from 3,000 miles away I would say you're off a tooth on the timing and that may have bent a valve. Unfortunately this is coming from personal experience :(

[czac]

thanks for the ideas all but as much as I hate to admit it, i figured out what was wrong. again, i pulled the spark plug just to see if it was wet , i was wondering if it was flooding or something so, as i looked at the plug i remembered i had cleaned it before putting it in after putting the head back on, and now, it was dirty looking and wet, so i wiped it off on my hand and realized it was oily soot... so i wiped it all off with a rag and cleaned it up, i put it back in, hit the decompression lever, choked it and pulled her over and boom, just like she used to, she fired up the first pull!

I could have kicked myself when I realized what happened... after cleaning the head, i shot some oil in the valves and all those areas to lube it up because i had no clue how long that old blown motor was sitting around. i now i had it in the garage since 2013 and who knows how long it sat outside at the guys house i bought the trike from.
I guess the oil got sucked down and onto the plug, after wipe it off it ran pretty good. it does pop and sputter some but i think the carb may need to be gone through yet again! i may break down and buy a new main jet and new needle valve and seat. One thing though, the pipe where it comes off the motor got cherry red in like 1 minute of running... it burned the paint off the new pipe! is it ok that it got so hot?

[yaegerb]

thanks for the ideas all but as much as I hate to admit it, i figured out what was wrong. again, i pulled the spark plug just to see if it was wet , i was wondering if it was flooding or something so, as i looked at the plug i remembered i had cleaned it before putting it in after putting the head back on, and now, it was dirty looking and wet, so i wiped it off on my hand and realized it was oily soot... so i wiped it all off with a rag and cleaned it up, i put it back in, hit the decompression lever, choked it and pulled her over and boom, just like she used to, she fired up the first pull!

I could have kicked myself when I realized what happened... after cleaning the head, i shot some oil in the valves and all those areas to lube it up because i had no clue how long that old blown motor was sitting around. i now i had it in the garage since 2013 and who knows how long it sat outside at the guys house i bought the trike from.
I guess the oil got sucked down and onto the plug, after wipe it off it ran pretty good. it does pop and sputter some but i think the carb may need to be gone through yet again! i may break down and buy a new main jet and new needle valve and seat. One thing though, the pipe where it comes off the motor got cherry red in like 1 minute of running... it burned the paint off the new pipe! is it ok that it got so hot?

Cherry red while idling that was noticeable? If so then jet fatter on pilot.

[czac]

Yeah pretty noticeable, that and the black paint on the pipe burned off in a minute also lol
So bigger jet on pilot ? What about the main jet?
Thanks!

[yaegerb]

Dunno about main yet. You said it turned cherry red while idling. Idle runs on pilot jet (circuit). Have you ensured there are no intake boot leaks or extra air getting to the intake?

[barnett468]

also check the ignition timing . insufficient timing can cause the exact same problem.

if your spark plug is new and pure white, it is screamin lean.

your popping could be from leaking valves . the valves could have easily been checked before you put the head on.



PREVIOUS KAWASAKI INTERNATIONAL R & D PROJECT ENGINEER AND ATV DEPARTMENT SUPERVISOR

[czac]

also check the ignition timing . insufficient timing can cause the exact same problem.

if your spark plug is new and pure white, it is screamin lean.

the plug is new-ish.... i just put it in this summer but didnt ride much due to all the problems i had with it this year... but i will pull it and look at it.


your popping could be from leaking valves . the valves could have easily been checked before you put the head on.

lol.. Could-a, would-a, should-a... you know how that goes!
I was too much in a rush to put her back together and get her running again...lol I hope its not the valves. For what its worth, everything looked good after i cleaned it up though, there wasnt anything noticeable that I may have seen just when cleaning it up....

[czac]

ok so the Pilot jet in the carb is a #20... what size should i go to next? a 25? a 30? also, my repair book for the trike says its got a 22MM carb but when i go on ebay and look at the pilot jets for a 22mm Mikuni carb, they look totally different than what i have. mine look like the jets that go in the 28MM mikuni carbs. are the jets different in todays carbs than they were back in 1985? also, how do i tell if i do have a 22MM or if it is a 28MM... what do i measure? is it the hole in the flanged end where it bolts to the motor?
thanks!

Oh yeah, here is a pic of the new BG pipe glowing red after sitting on idle for about 1-2 minutes...

https://photos.smugmug.com/Other/Yamaha-225-DXN/i-fdfb2Z6/0/L/IMG_8696-L.jpg

[czac]

a vid of it running and stalling lol

https://photos.smugmug.com/Other/Yamaha-225-DXN/i-mBJBqbK/0/960/IMG_8698.TRIM-960.mp4

[yaegerb]

What is the serial on the carb? Measure the inside diameter of the carb bell pointing towards the cylinder with a set of calipers.

[czac]

Ill have to check the serial#...
ok i will remeasure but I f my memory serves me, it was 26 mm

[muthey]

when searching for the jets make sure you put vm in front of your numbers and it should be a vm22 or you can use vm24, which uses the same type jets.